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how do i find the equations of the asymptotes given a function watch

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    function:

    2x+3/x-1
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    (Original post by SeekerOfKnowledge)
    function:

    2x+3/x-1
    Think about what values x cannot take. For another asymptote, think about what values y cannot take.
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    Hokey-koke.
    There are two types really:
    (i) vertical asymptotes
    (ii) horizontal asymptotes

    The "vertical asymptotes" are easy.
    Just find the x-coordinates that aren't possible, i.e. return an undefined value.
    So, in this case, \frac{2x+3}{x-1} will not be defined when you're dividing 2x+3 by 0.
    This is where x-1=0, meaning that there is a vertical asymptote at x=1.

    As for the horizontal asymptote, you just have to look what happens as x tends to infinity.
    So stick in really large positive and negative values and see what value you seem to get out.
    In this case, I think there will be a horizontal asymptote at y=2.
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    Well firstly, x can not equal 1.

    This is because if it did, you would divide by zero and we all know what happens when you divide by zero...

    THE ROOM BLOWS UP!!! :eek4:
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    thanks
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    (Original post by placenta medicae talpae)
    Hokey-koke.
    There are two types really:
    (i) vertical asymptotes
    (ii) horizontal asymptotes
    Not quite:

    Consider for example f(x) = x^2 + 4x + 9 - 5/(x-1)

    This function approach x^2 + 4x + 9 but never quite reaches there, so the quadratic is an asymptote to the function.
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    first use partial fractions:
    2x+3/x-1=2+5/x-1
    as x get big y-->2 horizontal aymptote @ y=2
    as x-->1,y-->infinity vertical asymtote @ x=1
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    (Original post by *MJ*)
    Well firstly, x can not equal 1.

    This is because if it did, you would divide by zero and we all know what happens when you divide by zero...

    THE ROOM BLOWS UP!!! :eek4:
    Your posts annoy me greatly. I don't know why, it just seems like you try far too hard to be funny whenever you post, when actually your humour is comparible to that of a 6 year old. Rant over.
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    (Original post by tomiswellcool)
    Your posts annoy me greatly. I don't know why, it just seems like you try far too hard to be funny whenever you post, when actually your humour is comparible to that of a 6 year old. Rant over.
    I thought this guy was funny! :woo:
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    (Original post by tomiswellcool)
    Your posts annoy me greatly. I don't know why, it just seems like you try far too hard to be funny whenever you post, when actually your humour is comparible to that of a 6 year old. Rant over.
    Do I know you? :curious:

    If not, **** off son.



    Happy new year. :dance:
 
 
 
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